Effect of the fungicide pyraclostrobin on the transcriptome of Africanized honey bees Apis mellifera during their foraging phase

Bees are crucial for maintaining wild areas, food production, and ecosystem balance. However, in recent years, these insects have been the subject of research due to concerns over their decline, potentially linked to the indiscriminate use of pesticides. Among pesticide classes, fungicides are the most frequently detected in bee products, with pyraclostrobin being one of the most commonly used active ingredients in agriculture, capable of causing harmful effects on bees. Therefore, this study aimed to evaluate the effect of lethal (LD50) and sublethal (LD50/100) doses of pyraclostrobin on gene expression profiles through transcriptomic analysis resulting from ingestion exposure in Africanized Apis mellifera honey bees during their foraging phase. Newly emerged bees were marked on the pronotum and returned to their respective colonies. After 21 days, 20 marked bees from each colony were collected, starved for 3 hours to empty their nectar sac contents, and subsequently fed honey syrup containing lethal (8.85 microgram/bee) and sublethal (0.0885 microgram/bee) doses of pyraclostrobin. Bees were collected at 1 and 4 hours post-exposure for transcriptomic analysis.